(Issue Hilary#303) Autosuggest for users and groups

* Changed general searches to use 'resourceTypes' param
* Changed autosuggest module to use 'data' param in $.getJSON
* Made auto-suggest for topnav search use includeIndirect=false
* Minor code-style house-cleaning
* Changed autosuggest for topnav to use $.ajax 'data' param
(Issue Hilary#303) Fixed up permissions and participants templates to account for both user and group objects
Brought in the documentviewer
Added z-index:0 to the document viewer

The document viewer top bar was appearing on top
on the overlays. This small CSS fix takes care
of that.
Cleaned up documentviewer dependency

Stripped out jquery and jquery UI as those are already in the page.
This reduces the size of the documentviewer dependency by about ~100KB

Addressed an issue in api.util.hideOnClickout which was using the wrong
jQuery variable.
Added jquery as a dependency to oae.api.content.js
(Paris2013) Initial work for PP images in activities.
(Paris2013) Adding multiple content items for content-related items
(Paris2013) Switch 'medium' to 'normal' for page previews.
(Paris2013) Add oae-threedots for the overlay link. Don't show mini-thumbnails for non-files
(ActivitiesPP) Cropping preview height, fixing comment indentation.
Merge pull request #2578 from mrvisser/issue-hilary-303

(Issue Hilary#303) Autosuggest for users and groups
Merge pull request #2590 from simong/documentviewer

Documentviewer
Merge pull request #2595 from mrvisser/activities-pp

Adding Content Previews to Activity wall.